<!doctype html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <script type="text/javascript" src="http://cdn.bootcss.com/jquery/3.1.1/jquery.js"></script>
    <title>Document</title>
</head>

<body>
    <button onclick="getDateDiff('2020-01-13 20:36:00')"> time </button>
    <script>
        var minute = 1000 * 60;
        var hour = minute * 60;
        var day = hour * 24;
        var halfamonth = day * 15;
        var month = day * 30;

        function getDateDiff(setdateTimeStamp) {
            console.log("1111")
            var dateTimeStamp = new Date(setdateTimeStamp);
            var now = new Date().getTime();
            var diffValue = now - dateTimeStamp;
            if (diffValue < 0) {
                //若日期不符则弹出窗口告之
                return "结束日期不能小于开始日期！";
            }
            var monthC = diffValue / month;
            var weekC = diffValue / (7 * day);
            var dayC = diffValue / day;
            var hourC = diffValue / hour;
            var minC = diffValue / minute;
            if (monthC >= 1) {
                result = "发表于" + parseInt(monthC) + "个月前";
            }
            else if (weekC >= 1) {
                result = "发表于" + parseInt(weekC) + "周前";
            }
            else if (dayC >= 1) {
                result = "发表于" + parseInt(dayC) + "天前";
            }
            else if (hourC >= 1) {
                result = "发表于" + parseInt(hourC) + "个小时前";
            }
            else if (minC >= 1) {
                result = "发表于" + parseInt(minC) + "分钟前";
            } else
                result = "刚刚";
            alert(result)
            return result;
        }
    </script>
</body>

</html>